Does vaginal estrogen cream pose a risk to my heart health?

DEAR DOCTOR K:

Vaginal estrogen cream cures my vaginal dryness. But I hear estrogen is risky for the heart. Should I be concerned?

DEAR READER:

Basically, I wouldn’t worry. Here’s why. Vaginal estrogen cream is one form of hormone therapy (HT). HT is estrogen taken alone or with other female hormones to treat the symptoms of menopause. “Systemic” HT involves hormones that enter the blood and travel throughout the body. It is the most effective treatment for postmenopausal hot flashes and vaginal symptoms, including vaginal dryness.

Systemic HT is medicine taken by mouth or through the skin by a skin patch or gel. From those locations, it enters the blood. But systemic HT carries with it a small risk of several serious conditions. In women who started menopause more than 10 years ago, there is an increased risk of heart attack and stroke. For all women, there is an increased risk of blood clots and breast cancer (when progestins are included with estrogen).

Low-dose vaginal estrogen is available in several forms: creams, tablets (such as Vagifem) and other kinds of vaginal rings. Creams, tablets and most vaginal rings act mostly in the vagina. They relieve vaginal symptoms, including vaginal dryness, burning, and pain with sexual intercourse. They do not relieve hot flashes.

Some vaginal estrogen creams are higher dose (more concentrated); some amount of estrogen is absorbed into the blood.

Those vaginal estrogen treatments that release little estrogen into the bloodstream have less risk of side effects than systemic estrogen. So far, no well-designed clinical trials have evaluated systemic risks, such as breast cancer or blood clots, of low-dose vaginal estrogen. But it’s likely that if there are such risks, they are much smaller than the risks related to systemic estrogen.

One complication of menopause that women don’t often think of is recurrent urinary tract infections (UTIs). Vaginal dryness not only causes vaginal symptoms such as discomfort during sex, but also encourages the growth of certain bacteria around the urethra — the tube that carries urine from the bladder to the vagina. If those bacteria get into the urethra, and then into the bladder, a UTI can start.

Apart from the high-dose Femring, vaginal estrogen is probably safe even over the long term. And if your main menopausal symptoms are vaginal symptoms, vaginal estrogen is just as effective as systemic HT and less risky. But talk to your doctor about the risks and benefits before you start — particularly if you have a history of breast cancer.

(This column is an update of one that ran originally in August 2013.)